When attempting to shape or machine (cut) a spherical internal surface on a workpiece, it is known to rotate the workpiece relative to a static cutting tool. However, difficulties arise with this configuration when the workpieces are large, and/or rotationally unbalanced. It would be desirable to provide a rotary tool for cutting at least a partial, or a full, spherical surface on an internal surface of a workpiece. It would be desirable to provide a rough cut and finish cut to machine (cut) the spherical internal surface in a single pass. It would be desirable to provide a rotary tool that was balanced during the cutting process. It would be desirable to provide a rotary tool supported for maximum stability while machining at least a partial spherical surface on an internal surface of a workpiece. It would be desirable to provide adjustability for a roughing insert and micro adjustability for a finishing insert. It would be desirable to provide a rotary tool that can be mounted on a sub-spindle, secondary spindle, or spindle computer numeric controlled lathe. It would be desirable to provide a rotary tool that can be used on a computer numeric controlled machining center. It would be desirable to provide a rotary tool that can be used on any type of equipment that has the capability to pull, push, or turn for rotary actuation to occur.